An Ioun stone is named after Ioun, a god of knowledge and prophecy revered on some worlds. Many types of Ioun stone exist, each type a distinct combination of shape and color.
When you use an action to toss one of these stones into the air, the stone orbits your head at a distance of 1d3 feet and confers a benefit to you. Thereafter, another creature must use an action to grasp or net the stone to separate it from you, either by making a successful attack roll against AC 24 or a successful DC 24 Dexterity (Acrobatics) check. You can use an action to seize and stow the stone, ending its effect.
A stone has AC 24, 10 hit points, and resistance to all damage. It is considered to be an object that is being worn while it orbits your head.
Absorption (Very Rare). While this pale lavender ellipsoid orbits your head, you can use your reaction to cancel a spell of 4th level or lower cast by a creature you can see and targeting only you.
Once the stone has canceled 20 levels of spells, it burns out and turns dull gray, losing its magic. If you are targeted by a spell whose level is higher than the number of spell levels the stone has left, the stone can't cancel it.
Agility (Very Rare). Your Dexterity score increases by 2, to a maximum of 20, while this deep red sphere orbits your head.
Awareness (Rare). You can't be surprised while this dark blue rhomboid orbits your head.
Fortitude (Very Rare). Your Constitution score increases by 2, to a maximum of 20, while this pink rhomboid orbits your head.
Greater Absorption (Legendary). While this marbled lavender and green ellipsoid orbits your head, you can use your reaction to cancel a spell of 8th level or lower cast by a creature you can see and targeting only you.
Once the stone has canceled 50 levels of spells, it burns out and turns dull gray, losing its magic. If you are targeted by a spell whose level is higher than the number of spell levels the stone has left, the stone can't cancel it.
Insight (Very Rare). Your Wisdom score increases by 2, to a maximum of 20, while this incandescent blue sphere orbits your head.
Intellect (Very Rare). Your Intelligence score increases by 2, to a maximum of 20, while this marbled scarlet and blue sphere orbits your head.
Leadership (Very Rare). Your Charisma score increases by 2, to a maximum of 20, while this marbled pink and green sphere orbits your head.
Mastery (Legendary). Your proficiency bonus increases by 1 while this pale green prism orbits your head.
Protection (Rare). You gain a +1 bonus to AC while this dusty rose prism orbits your head.
Regeneration (Legendary). You regain 15 hit points at the end of each hour this pearly white spindle orbits your head, provided that you have at least 1 hit point.
Reserve (Rare). This vibrant purple prism stores spells cast into it, holding them until you use them. The stone can store up to 3 levels worth of spells at a time. When found, it contains 1d4−1 levels of stored spells chosen by the GM.
Any creature can cast a spell of 1st through 3rd level into the stone by touching it as the spell is cast. The spell has no effect, other than to be stored in the stone. If the stone can't hold the spell, the spell is expended without effect. The level of the slot used to cast the spell determines how much space it uses.
While this stone orbits your head, you can cast any spell stored in it. The spell uses the slot level, spell save DC, spell attack bonus, and spellcasting ability of the original caster, but is otherwise treated as if you cast the spell. The spell cast from the stone is no longer stored in it, freeing up space.
Strength (Very Rare). Your Strength score increases by 2, to a maximum of 20, while this pale blue rhomboid orbits your head.
Sustenance (Rare). You don't need to eat or drink while this clear spindle orbits your head.
This other set of Ioun Stones come from the Extra Life Adventure: Lost Laboratory of Kwalish.
Supreme Intellect (Rare). You gain a +1 bonus to Intelligence checks while this faceted sphere orbits your head.
Historical Knowledge (Rare). You gain proficiency in the History skill, or a +1 bonus to checks with that skill if already proficient, while this polished, steely sphere orbits your head.
Natural Knowledge (Rare). You gain proficiency in the Nature skill, or a +1 bonus to checks with that skill if already proficient, while this burnished, brassy stone orbits your head.
Religious Knowledge (Rare). You gain proficiency in the Religion skill, or a +1 bonus to checks with that skill if already proficient, while this tiny golden gem orbits your head.
Language Knowledge (Rare). You are fluent in one additional language while this pulsating bit of red jeweled crystal orbits your head. The DM chooses the language bestowed by the stone.
Self-Preservation (Rare). You gain a +1 bonus to Intelligence saving throws while this silvery gem orbits your head.
Notes: Bonus: Armor Class, Bonus: Strength Score, Bonus: Dexterity Score, Bonus: Constitution Score, Bonus: Intelligence Score, Bonus: Wisdom Score, Bonus: Charisma Score, Bonus: Hit Points, Buff, Detection, Utility, Warding
Dungeon Masters, be advised of inconsistent lore of Ioun stones.
As 5th edition lore states about Ioun as a Loose Pantheons goddess, where she is presented on 4th edition Dawn War pantheon.
The Forgotten Realms universe has previously provided resources of some lore about their origins. Dragon#174 issue mention them as naturally growing stones in Quasi-Elemental Plane of Minerals. Current (1491 DR) cosmology structure doesn't mention anything about such plane.
Netheril: Empire of Magic - Encyclopedia Arcana (page 5) brings lore about one of if not the greatest arcanist of ancient Netherril empire: Congenio Ioun. This is most likely version of stone origins as it fits current Forgotten Realms setting, despite huge gap of information about them from ancient times (around -3300 DR).
Of course, everything is on Dungeon Masters behalf, but as long as anyone might be interested in lore of Ioun stones, I provided here enough details and references where to do research.
Thanks!
It doesnt specify what happens when it is destroyed...
I would imagine that's up to DM Fiat like many things in 5e. If the party has a wizard maybe they could fix it with enough time, and magic. Or maybe its glorious effects are lost forever. Or maybe even a Cleric of Knowledge or Arcane could fix it as well.
Does the stone of insight GLOW? I read the word "incandescent" to my DM and based on the description of that particular stone as presented on Beyond, we agreed in the session I attuned to it that it glows, blowing my stealth. But reading the descriptions of all the stones, it seems each has a color and an adjective before it. I think my DM is on board with it not glowing, but does anyone have any evidence for or against?
Is it possible to have multiple of the same ioun stone? EG: 2 stones of protection for +2 AC?
bc they are items that require attunement I would allow them to stack. However, if they gave benefits without you being attuned to them then I would say they shouldn't probably stack.
However, in Forgotten Realms lore there is a real wacky dude named Larloch who had over two dozen ioun stones floating around his head, and while he hasn't been used in like a decade by WotC, I think he's still as cool as can be and when one of my players find an ioun stone they do start seeing him in their dreams.
No it’s not you can have several ioun stones but everything basically says you get a bonus once and once only.
And if I have 2 different types? say protection and mastery?
As I read it yes. Up to 3 but the if they require attuned those are your three attuned items.
When two stones of the same effect are in close proximity they are repelled by each other. But ultimately it's up to the DM to keep it balanced. Since they require attunement players can only have up to 3 stones attuned and thats only possible without any other magical equipment attuned.
So I make a ranger with the Ioun Stone of Sustenance. I use "Hide In Plane Sight" class feature to get a +10 to my roll. I then roll a stealth check with expertise in stealth and maximum dexterity for an additional +17 to my stealth check. If I roll a 15, I have a total or 42 for my stealth check. As long as I don't move I can maintain that 42 stealth and as long as I have the Ioun Stone of Sustenance I won't ever need to move and I can stay hidden. Here's the thing...the Ioun Stone is this floating magical stone that orbits my head...so mechanically there's nothing saying I'm easier to spot with an Ioun Stone floating above my head but common sense would dictate that someone may not be able to spot me because my camouflage skills are so great, but they could totally spot the stone orbiting above my head...right?
Actually that same boxed set it when it talks about Ioun's death it mentions "it is said to the realms of the gods" ever since they made ioun a deity in the 4th ed setting I imagined this confirmed that. As to why he didn't become a god in his home crystal sphere? Idk. Maybe he served Mystral or something until Karsus Folly. Either way the only descrepency really for this is Matt Mercer's referral to Ioun as her in his Exandria setting. But I imagine that's more to do with their political viewpoints than any preconceptions of Ioun as the Netherese Arcanist. Either way, it would be cool to bring him back to the realms as a deity in his own right.
As far as Larloch having all his stones active at once, that was still technically during the 4ed timeline before the sundering so that would still work.
17+15 is 32, not 42
dont forget the "hide in plain sight" feature that adds +10, making it 42. 17+15+10 = 42
Can you please tell me where that info is? I don't see it in the description block.
Now we just need a guantlet to hold these guys and then you can reskin the stones as infinity stones
By the definition of the word incandescent, it only glows when heated.
Have? Sure.
Attune to? Nope, no repeat items rule.